不同速度流失之高強度半蹲舉對垂直跳表現的急性影響

Acute effects of heavy half squat with different velocity loss on vertical jump performance

緒論：高強度阻力訓練（≥85%最大反覆次數[85% of 1 repetition maximum, 85%1RM]）可以提升隨後的運動表現，稱之為活化後增能作用（post-activation potentiation , PAP）。速度依循訓練（velocity-based training, VBT）可透過設定訓練時的向心速度流失（velocity loss, VL）比例控制訓練量以及疲勞程度。然而，目前低（5-20%）、高（>20%） VL對於垂直跳的PAP誘發效果仍不清楚。因此，本研究目的為探討低、高VL下肢高強度阻力訓練對後續下蹲跳（countermovement jump, CMJ）表現的急性影響。方法：招募12名有阻力訓練經驗的年輕男性（年齡：21.0±0.8歲；身高：175.1±2.9公分；體重：70.9±6.0公斤），以交叉設計（crossover designs）、平衡次序方法（counterbalancing method）進行3組速度流失20% （VL20）或30% （VL30）、強度90%1RM的半蹲舉（halfsquat, HS），在HS訓練前以及訓練後第7分鐘進行CMJ測驗。以重複量數二因子變異數（two-way repeated measured ANOVA）進行統計分析。信心水準設定為α= .05。結果：CMJ各項參數經過二因子統計分析，沒有交互作用存在（p > .05）。後續進行主要效果分析，結果顯示在組別因子（p > .05）以及時間因子（p > .05）皆沒有顯著差異。結論：本研究結果指出VL20、VL30進行高強度HS皆無法有效提升訓練後第7分鐘的CMJ表現。因此，教練、運動員以誘發PAP效應為訓練目的時，進行高強度HS應避免設定> 20%的速度流失。建議未來研究可以探討其他速度流失閾值（如：5%、10%、15%）的PAP效果，以期望建構出VBT誘發下肢PAP效果的有效處方。

Introduction: High-intensity resistance training (≥85% of one repetition maximum [85%1RM]) can enhance subsequent exercise performance. This phenomenon has been termed post-activation potentiation (PAP). Velocity-based training (VBT) controls training volume and fatigue by setting the proportion of concentric velocity loss (VL) during training. However, the effects of low (5–20%) and high (> 20%) VL on vertical jump performance are still unknown. Therefore, the present study aimed to examine the acute effects of high-intensity resistance training with a low or high VL percentage on subsequent countermovement jump (CMJ) performance in resistance-trained young males. Methods: Twelve resistance-trained young males (age 21.0±0.8 years; height 175.1±2.9 cm; body mass 70.9±6.0 kg) were recruited. The experiment had a crossover design and followed a counterbalancing method, where each participant performed three sets of half squat (HS) with 90%1RM at a 20% (VL20) or 30% (VL30) decrease in mean concentric velocity. The CMJ was performed before (pretest) and 7 minutes after (post-test) HS. A two-way repeated measures ANOVA (group [VL20 vs. VL30]×time [pre-test vs. post-test]), with the Bonferroni post-hoc test, was performed for each dependent variable. Statistical significance was accepted at theα= .05 level. Results: No significant group×time interactions were observed in the two-way repeated measures ANOVA for any of the CMJ parameters (p > .05). No significant main effects of group or time were observed for CMJ performance (p > .05). Conclusion: This study found that high-intensity HS with low (20%) or high (30%) VL was ineffective in improving CMJ performance. Therefore, when coaches and athletes aim to induce the PAP effect during training, it is important to avoid setting a VL threshold > 20% for high-intensity HS. Future research should explore different VL thresholds (e.g., 5%, 10%, and 15%) to construct an effective VBT training prescription for enhancing CMJ performance.